1. Field of the Invention
The present invention relates to a detection apparatus and a detection method for a droplet discharge apparatus provided with a discharge head having a discharge nozzle capable of discharging droplets, and a droplet discharge apparatus.
Priority is claimed to Japanese Patent Applications No. 2002-312578, filed Oct. 28, 2002, and No. 2003-297878, filed Aug. 21, 2003, which are incorporated herein by reference.
2. Description of Related Art
Heretofore, photolithographic methods are used, primarily, for manufacturing devices with fine patterns. However, in recent years, attention has been given to a device manufacturing method using a droplet discharge system. In this technique, liquid material containing functional material is discharged from a discharge head in a droplet discharge apparatus, placing the material on a substrate in order to form a pattern, and it is very effective from the standpoint of handling diversified small-quantity production. For a droplet discharge system in a droplet discharge apparatus, generally known systems are a piezo jet system in which a droplet of liquid material is discharged by the distortion of a piezoelectric element, or a method in which liquid material is discharged by the rapid generation of steam due to the application of heat.
A discharge head has a plurality of discharge nozzles. However, sometimes liquid material cannot be discharged from some of the discharge nozzles because of clogging, or the like, for example. If there is a discharge nozzle (non-performing nozzle) that cannot discharge droplet, then dots will be missing when a dot pattern is formed by discharging droplets onto a substrate. Japanese Patent Application Laid-Open, No. 11-78051 discloses a technique regarding a method of detecting missing dots (non-performing nozzle detection method) in relation to a printer (printing device). In this technique, an ink droplet is discharged from an ink nozzle such that it passes through the detection region of a photo sensor, and it is determined whether the ink droplet is discharged from the ink nozzle based on a drop in the amount of light received by the photo sensor.
The above-described conventional art is effective because it can detect accurately whether an ink droplet is discharged from an ink nozzle or not, without improving sensor sensitivity, by adjusting the amount of ink discharged in droplets per unit time, or the discharge interval. However, in a case where only the discharge amount is increased or the discharge interval is shortened, there is a possibility that detection of ink droplets cannot be performed accurately by a photo sensor.
The present invention takes such conditions into consideration, with an object of providing a detection apparatus and a detecting method for a droplet discharge apparatus that can perform accurate detection when detecting whether a droplet is discharged from a discharge nozzle of the droplet discharge apparatus, and a droplet discharge apparatus.